12122111121 has 4 divisors (see below), whose sum is σ = 16162814832. Its totient is φ = 8081407412.

The previous prime is 12122111117. The next prime is 12122111159. The reversal of 12122111121 is 12111122121.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 12122111121 - 2² = 12122111117 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 12122111121.

It is not an unprimeable number, because it can be changed into a prime (12122111101) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2020351851 + ... + 2020351856.

It is an arithmetic number, because the mean of its divisors is an integer number (4040703708).

Almost surely, 2^12122111121 is an apocalyptic number.

It is an amenable number.

12122111121 is a deficient number, since it is larger than the sum of its proper divisors (4040703711).

12122111121 is an equidigital number, since it uses as much as digits as its factorization.

12122111121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4040703710.

The product of its digits is 16, while the sum is 15.

Adding to 12122111121 its reverse (12111122121), we get a palindrome (24233233242).

It can be divided in two parts, 1212211 and 1121, that multiplied together give a palindrome (1358888531).

The spelling of 12122111121 in words is "twelve billion, one hundred twenty-two million, one hundred eleven thousand, one hundred twenty-one".